Typical spin-on fluid filters according to some prior art designs are mounted to the mounting head by the use of an internally-threaded metal nut plate. The nut plate is anchored to the filter shell and includes at least one flow inlet and a flow exit. A spin-on filter with a nut plate often includes a large number of components that are required to form the filter which increases the cost and assembly complexity of the filter.
Some known spin-on fluid filters eliminate the nut plate. Examples include U.S. Pat. Nos. 7,434,697 and 7,614,504.
Whether or not the spin-on filter includes a nut plate, sealing must be provided between the head and the filter to prevent leakage outside the filter to environment, and sealing must be provided between the flow inlet and the flow exit to prevent leakage of unfiltered fluid from the inlet to the filtered fluid outlet. These sealing functions are typically provided by separate parts of the filter, including the use of installed sealing gaskets.
Improvements to spin-on filters are desirable.